23209951978444 has 144 divisors (see below), whose sum is σ = 51652999157760. Its totient is φ = 9023767200000.

The previous prime is 23209951978441. The next prime is 23209951978471. The reversal of 23209951978444 is 44487915990232.

It is a super-2 number, since 2×23209951978444² (a number of 28 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 23209951978444.

It is not an unprimeable number, because it can be changed into a prime (23209951978441) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2397965197 + ... + 2397974875.

It is an arithmetic number, because the mean of its divisors is an integer number (358701383040).

Almost surely, 2^{23209951978444} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 23209951978444, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25826499578880).

23209951978444 is an abundant number, since it is smaller than the sum of its proper divisors (28443047179316).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

23209951978444 is a wasteful number, since it uses less digits than its factorization.

23209951978444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11940 (or 11931 counting only the distinct ones).

The product of its (nonzero) digits is 156764160, while the sum is 67.

The spelling of 23209951978444 in words is "twenty-three trillion, two hundred nine billion, nine hundred fifty-one million, nine hundred seventy-eight thousand, four hundred forty-four".